Vertebrate Paleontology 3D Database

 

 

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Now showing 1 - 10 of 40
  • Publication
    The Slothful Claw: Osteology and Taphonomy of Nothronychus mckinleyi and N. graffami (Dinosauria: Theropoda) and Anatomical Considerations for Derived Therizinosaurids
    (2015-06-10) Hedrick, Brandon P; Zanno, Lindsay E; Dodson, Peter; Wolfe, Douglas G
    Nothronychus was the first definitive therizinosaurian discovered in North America and currently represents the most specialized North American therizinosaurian genus. It is known from two species, No. mckinleyi from the Moreno Hill Formation (middle Turonian) in west-central New Mexico, and No. graffami from the Tropic Shale (early Turonian) in south-central Utah. Both species are represented by partial to nearly complete skeletons that have helped elucidate evolutionary trends in Therizinosauria. In spite of the biogeographical and evolutionary importance of these two taxa, neither has received a detailed description. Here, we present comprehensive descriptions of No. mckinleyi and No. graffami, the latter of which represents the most complete therizinosaurid skeleton known to date. We amend previous preliminary descriptions of No. mckinleyi and No. graffami based on these new data and modify previous character states based on an in-depth morphological analysis. Additionally, we review the depositional history of both specimens of Nothronychus and compare their taphonomic modes. We demonstrate that the species were not only separated geographically, but also temporally. Based on ammonoid biozones, the species appear to have been separated by at least 1.5 million years and up to 3 million years. We then discuss the impacts of diagenetic deformation on morphology and reevaluate potentially diagnostic characters in light of these new data. For example, the ulna of No. mckinleyi is curved whereas the ulna of No. graffami was considered straight, a character originally separating the two species. However, here we present the difference as much more likely related to diagenetic compression in No. graffami rather than as a true biologic difference. Finally, we include copies of three-dimensional surface scans of all major bones for both taxa for reference.
  • Publication
    Nothronychus graffami Right Fibula
    (2015-01-14) Hedrick, Brandon P
    UMNH VP16420 fibula
  • Publication
    Surface Scan of the Femur of CPC 274
    (2016-03-11) Hedrick, Brandon P
    CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
  • Publication
    Nothronychus graffami Right Ulna
    (2015-01-07) Hedrick, Brandon P
    UMNH VP16420 ulna
  • Publication
    Nothronychus graffami Ischium
    (2015-01-11) Hedrick, Brandon P
    UMNH VP16420 ischium
  • Publication
    Nothronychus mckinleyi Fibula
    (2015-01-25) Hedrick, Brandon P
    MSM P2117 fibula
  • Publication
    Surface Scan of the Dorsal Vertebra of CPC 274
    (2016-03-11) Hedrick, Brandon P
    CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).
  • Publication
    Nothronychus graffami Manual Ungual
    (2015-01-09) Hedrick, Brandon P
    UMNH VP16420 manual claw
  • Publication
    Nothronychus mckinleyi Right Tibia
    (2015-01-24) Hedrick, Brandon P
    MSM P2117 right tibia
  • Publication
    Surface Scan of the Parietal Fragment 2 of CPC 274
    (2016-03-11) Hedrick, Brandon P
    CPC 274, a new centrosaurine specimen from Mexico, was unearthed in northern Coahuila from 2007-2011. The majority of elements that were found with CPC 274 were surface scanned using a Polhemus FastSCAN system in order to allow readers the ability to manipulate the bones in a 3D environment to assess features directly. The files are .obj files and can be visualized in MeshLabTM, which can be downloaded for free (MeshLab, Visual Computing Lab – ISTI – CNR http://meshlab.sourceforge.net/).